Sealing ring

ABSTRACT

Sealing ring includes an annular member of creep-resistant material formed with at least one pair of projecting webs defining an annular depression therebetween, and metal material received in the annular depression, the metal material having the properties of creeping under given stress conditions and of adhering to the creep-resistant material of the annular member.

1 51 Sept. 12, 1972 United States Patent Porner et al.

541 SEALING RING 560,309 5/1896 White....................220/46 MS [72]Inventors: Hum Pom"; Hummer Schabem 2,695,184 11/1954Hobbs.........,.........220l46 MS R9b9l'l Weber, all of Erlansen,FOREIGN PATENTS OR APPLICATIONS many [73] Assignee: SiemensAktiengesellschaft,

712,786 7/1954 GreatBritain.........277l235A Berlin, Germany PrimaryExaminer'-Robert l. Smith Attorney-Curt M. Avery, Arthur E. Wilfond,Herbert 221 Filed: April 3,1970

21 Appl.No.: 25,460

L. Lerner and Daniel J1 Tick 7] ABSTRACT Sealing ring includes anannular member of creep-re- UNITED STATES PATENTs 3,197,218 7/1965Coulter .................220/46 MS 10 Claims, 5 Drawing FigIII'esPATENTED SEP 12 I912 Fig.

SEALING RING problem, especially if the opening and closing operationisfully automated, such as when fuel elements are changed orcooling-passage closures are opened. In such cases, scratches orindentations may be formedin the seals due to the presence of dirt inthe circulating medium or other contamination, when the seals areremoved from theassembly. Seals formed with such indentations andscratches are not always effective forreuse. I

It is accordingly an object of the present invention to provide asealing ring which, on the one hand, offers effective sealing and, onthe other hand, even under repeated use assures that any'damagetheretois compensated for without negatively effecting the sealing actionthereof. r

With theforegoing and other objects in view, we provide, in accordancewith our invention, sealing ring comprising an annular member ofcreep-resistant material formed with at least one pair of projectingwebs defining an annular depression therebetween, and metal materialreceived in the annular depression, the metal material having theproperties of creeping under given stress conditions and of adhering tothe creep-resistant material of the annular member.

After the sealing ring of our invention has been installed in anassembly, high operating pressure causes the softmetal in the depressionor groove to creep or flow and completely fill the groove, all scratchesor indentations being filled and rendered ineffective. The groove thusacts asa so-called flow-bed.

In accordance "with a further feature of the invention, therefore, thewalls or webs defining the depression or groove, are of such narrowwidth with respect to the width of the depression or flow-bed that thepressure exerted on the seal is absorbed mainly by the sealing metal inthe flow-bed or groove. The strength of the webs is increased byproviding them with sloping sides, in accordance with an added featureof the invention.

According to additional feature of the invention, the sealing ring isformed of steel or steel alloy of high creep-resistance and the sealingmetal in the depression or flow-bed consists of gold or silver.

In accordance with a concomitant feature of our invention, we providesealing ring usable in many applications, wherein the outer surface ofthe sealing ring is substantially cylindrical and the inner surfacethereof is conical.

Moreover, in order to assure uniform distribution of the sealing metal,in accordance with another feature of our invention, we provide sealingring, which, at least in the region of the sealing edge thereof, has asubstantially uniform coating of the sealing metal, the

coating being of such thickness that the flow-bed is completely filledwhen a sealing force is applied to the sealing ring.

the level of the center one of the three grooves acting as a flow-bed,In the event of the production of high internal pressure in the assemblyto be sealed, the flat annular ridge exerts pressure on the flow-bed andthe defining webs thereof, forcingthe sealihg metal received in theflow-bed against an outer sealing-channel wall ofthe assembly. I

To avoid contamination of thex-flow-bed, in ac-.

cordance with a further feature of our invention, we.

provide our sealing ring' with an additional web or flange formed abovethe flow-bed proper and serving as a dirt collector. I I

In accordancejwith an added feature of the invention, we provide oursealing ringwith two flow-bed grooves one behind the other, with anannular groove located therebetween to trap leakage.

Other features which are considered as characteristic for the inventionareset forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin sealing ring, it is nevertheless not intended to be limited to thedetails shown, since various modifications and structural changes may bemade therein without departing from the spirit of the invention andwithin the scope and range of theequivalents of the claims. Theconstruction and method of operation of the invention, however, togetherwith additional objects and advantages thereof, will be best understoodfrom the following description of specific embodiments when read inconnection with the accompanying drawing, in

which: I I

FIG. 1 is a sectional view of a flow-bed in a sealing ring constructedinaccordance with our invention;

FIG. 2 is a half-sectional view of an embodiment of our sealing ringhaving radially disposed sealing surfaces;

FIG. 3 is a half-sectional view of another embodiment of the sealingring having a cylindrical outer sealing surface;

FIG. 4 is a much-enlarged fragmentary view of a installation thereof inan assembly to be sealed; and

FIG. 5 is another view of FIG. 4 showing the sealing ring installed inthe assembly.

Referring now to the drawing and first particularly to FIG. 1 thereof,there is shown a section of a sealing ring 1, after it has beeninstalled. The sealing ring is provided with a V-shaped depression orgroove 2, into which prior to installation there is inserted a ring 3,of silver for example, serving as the sealing material. Afterinstallation of the sealing ring 1, the silver ring 3 is pressed againstan outer wall 4 of an assembly component, so that that it completelyfills the depression or groove 2 and flows out laterally over webs 5 and6, which define the groove. The groove 2 acts as a flowbed, because thesealing metal 3 can expand freely in the peripheral direction of thesealing ring 1 within the flow-bed and is also pressed all over tightlyagainst the outer wall 4. It is advantageous in this regard that theland width of webs 5 and 6 be small in relation to the width of theflow-bed or groove 2, so that the sealing force is appliedessentially bythe sealing metal in the flow-bed to the surfaces to be sealed. It isalso of advantage that the pressure on the sealing ring 1, after thesealing ring has been installed, be sufficiently high that the walls orwebs 5 and 6 are deformed slightly at the lands thereof. This highpressure exerted on the lands of the webs 5 and 6 also assures theprevention of the sealing metal 3 from flowing away axially.

FIG. 2 discloses a flat sealing ring 7 which, for example, affordsradial sealing between a horizontal upper and lower surface. Flowable orcreepable. sealing materials are inserted into respective depressions orgrooves 8, to, ensure effective sealing. Webs or walls 9 prevent thesealing metal from flowing away in the radial direction of th e'sealingring 7. With the embodiment of FIG. 2 it is possible to employ-only oneflow-bed for each sealing ring. Whenseveral flow-beds are disposed sideI by side, l the gaps 10 which are located therebetween can be used fortrapping or absorbing leakage. I

In FIG. 3, there is shown a sealing ring 11 having a cylindricaloutersealing surface 12. A depression or groove 2 corresponding to the groove2 shown in FIG. 1 is filled with a sealing metal and acts as a flow-bed.

, FIGS. 4 and 5 illustrate a special embodiment of the sealing ring ofour invention which is particularly suitable for closing of coolingducts or channels in nuclear reactors. The sealing ring 11, only asection of which in the region of the sealing surface thereof is shownin order to simplify the drawing, has a slightly conical outer surface12 which, after the sealing ring has been tightened in the assembly,takes a cylindrical form, and also has an inner surface 13 taperingsharp in a downward direction. After being installed in the assembly,the outer surface of the sealing ring 11 is disposed adjacent a housing4 of the assembly and is held down from above by a clamping nut 15 ofthe assembly. Actual clamping pressure is produced by a stopper or plug16 located at the inside of the sealing ring 11 and by pressure existingwithin the pressure chamber 17 of the reactor assembly housing 4.

As shown in FIG. 4, the entire surface of the sealing ring 11 isprovided with a uniform layer 18 of silver. In the lower part of thecylindrical outer surface 12 of the sealing ring 11 there are formedthree annular depressions or grooves 19, 20 and 21 defined by webs orwalls 22 and 23 which have an outside diameter greater by about twicethe thickness of the silver layer 18 than the cylindrical part 12 of thesealing ring 11. The inner surface of the sealing ring 11 is providedwith a ridge 24 at the level of the central depression or groove 20.

As shown in FIG. 5, after the sealing ring 11 has been installed in theassembly, mechanical clamping force and the operating pressure actingupon an inner stopper or plug 16 force the sealing ring 11 against aninner wall 4 of a duct that is to be sealed. The silver on theprojecting webs or walls 22 and 23 is caused to flow partly into thecentral depression 20, and a flow-bed 25 is formed with an increase inthe thickness of the silver coating or layer at that location. Some ofthe silver, however, flows into depressions or grooves 19 and 21 whichare provided for just that purpose to receive the excess silver and toprevent thereby the formation of blobs. In the central depression 20,completely filled with silver, the silver is under a very high excesspressure resulting from the correspondingly high bearing pressureexerted thereon. The ridge 24 on the inside of the sealing ring 11,especially due to the location thereof on the level with the flow-bed 25provides a desirable introduction of outwardly spreading force into thering 11 and a concentration of the bearing pressure within the region ofthe flow-bed 25. Since the silver in the flow-bed 25 is prevented fromflowing away in the axial direction of the sealing ring 11 by theprojecting webs 22 and 23, it'consequently tends to flow about theperiphery of the sealing ring 11, thereby filling any scratches formedinthe duct sealing surface 4 or in the flow-bed surface 25 of the ring 11,with silver. Depending upon the number and depth of any scratches orimperfections appearing in the respective surfaces that are to besealed, the sealing ring 11 may he often reused.

minimum. It is furthermore possible, in accordance with the invention,to coat the sealing ring with other materials than silver, such as goldor other materials having creep properties, or also to produce theflowbed by soldering-in a wire which spreads when the sealing ring isclamped. Plastic materials can also be used as the material having creepproperties.

With the aforedescribed sealing ring of our invention it is possiblealso to reduce the sealing ring rapidly, even when numerous scratches orimperfections are made therein by granular impurities. Moreover, theSealing ring of our invention can be used not only for nuclear reactorcooling-duct closures mentioned hereinbefore by way of example but inall kindsof liquid and gas circulatory loops having high concentrationwhich causes corrosive'wear and thereby eventually damage to the sealingrings and to the seats for the sealing rings when the sealing rings areremoved and re-installed.

-We claim:

1. Sealing ring comprising an annular member of creep-resistant materialhaving a sealing surface formed with at least one pair of websprojectingoutwardly from said sealing surface and defining an annulardepression therebetween, and metal material received in said annulardepression and extending .outwardly beyond said webs, said metalmaterial having the properties of creeping under given stress conditionsand of adhering to the creep-resistant material of said annular member.

2. Sealing ring according to claim 1, wherein said webs are of suchnarrow width with respect to the width of said depression definedthereby, that bearing pressure of the sealing ring is absorbed mainly bythe metal material in said depression.

3. Sealing ring according to claim 1, wherein said webs have slopingsides.

4. Sealing ring according to claim 1, wherein said creep-resistantmaterial of said annular member is selected from the group consisting ofsteel and steel alloys, and said metal material received in saiddepression is selected from the group consisting of gold and silver.

5. Sealing ring according to claim 1, wherein said annularmember has asubstantially cylindrical outer surface and a substantially conicalinner surface.

6. Sealing ring according to claim 1, wherein said annular member atleast in the region thereof engageable with a surface so as to form aseal therewith when sealing pressure is applied to the sealing ring, iscovered with a substantially uniform coating of said metal material,said coating being of such thickness as to creep, upon application ofsaid sealing pressure to the sealing ring, into said depression insufficient quantity as to completely fill said depression.

7. Sealing ring according to claim 6, wherein two additional annulardepressions are formed in said annular member and are located adjacentsaid first-mentioned annular depression on opposite sides of said pairof projecting webs, and said webs extend from the outer surface of saidannular member for a distance about twice the thickness of said coatingof metal material.

8. Sealing ring according to claim 7, wherein said annular member has asubstantially conical inner surface fonned with an annular ridge at alevel thereof opposite the annular depression located centrally of saidtwo ad ditional annular depressions.

9. Sealing ring according to claim 1, wherein said groove is located atan inner end of the sealing ring, and including an additional annularweb projecting from said annular member at a side of said depressiontoward the outer end of the sealing ring to serve as a dirt collector.

l0. Sealing ring according to claim 1, wherein said annular member isformed with another annular depression disposed coaxially to saidfirst-mentioned depression and separated therefrom by an annular gapformed in said annular member for absorbing leakage.

1. Sealing ring comprising an annular member of creep-resistant materialhaving a sealing surface formed with at least one pair of websprojecting outwardly from said sealing surface and defining an annulardepression therebetween, and metal material received in said annulardepression and extending outwardly beyond said webs, said metal materialhaving the properties of creeping under given stress conditions and ofadhering to the creep-resistant material of said annular member. 2.Sealing ring according to claim 1, wherein said webs are of such narrowwidth with respect to the width of said depression defined thereby, thatbearing pressure of the sealing ring is absorbed mainly by the metalmaterial in said depression.
 3. Sealing ring according to claim 1,wherein said webs have sloping sides.
 4. Sealing ring according to claim1, wherein said creep-resistant material of said annular member isselected from the group consisting of steel and steel alloys, and saidmetal material received in said depression is selected from the groupconsisting of gold and silver.
 5. Sealing ring according to claim 1,wherein said annular member has a substantially cylindrical outersurface and a substantially conical inner surface.
 6. Sealing ringaccording to claim 1, wherein said annular member at least in the regionthereof engageable with a surface so as to form a seal therewith whensealing pressure is applied to the sealing ring, is covered with asubstantially uniform coating of said metal material, said coating beingof such thickness as to creep, upon application of said sealing pressureto the sealing ring, into said depression in sufficient quantity as tocompletely fill said depression.
 7. Sealing ring according to claim 6,wherein two additional annular depressions are formed in said annularmember and are located adjacent said first-mentioned annular depressionon opposite sides of said pair of projecting webs, and said webs extendfrom the outer surface of said annular member for a distance about twicethe thickness of said coating of metal material.
 8. Sealing ringaccording to claim 7, wherein said annular member has a substantiallyconical inner surface formed with an annular ridge at a level thereofopposite the annular depression located centrally of said two additionalannular depressions.
 9. Sealing ring according to claim 1, wherein saidgroove is located at an inner end of the sealing ring, and including anadditional annular web projeCting from said annular member at a side ofsaid depression toward the outer end of the sealing ring to serve as adirt collector.
 10. Sealing ring according to claim 1, wherein saidannular member is formed with another annular depression disposedcoaxially to said first-mentioned depression and separated therefrom byan annular gap formed in said annular member for absorbing leakage.